{
  "abstract": "Complex systems in engineering, biology and materials science frequently exhibit critical‑state behaviours and emergent functions originating from molecular‑level solid‑liquid‑interface interactions. These interactions alter molecular conformations, redistribute excited‑state energy and reorganize interfacial hydration layers. Investigating such critical dynamics demands in‑situ sensing tools capable of time‑resolved tracking of molecular recognition within highly turbid real‑world biological matrices. Conventional molecular interaction techniques including SPR, BLI and FRET/LRET suffer from intrinsic limitations. SPR/BLI deliver indirect mass‑based signals and cannot report ligand conformational changes or interfacial hydration evolution. FRET/LRET strictly requires donor‑acceptor spectral overlap, restricting probe design. Moreover, these methods mostly rely on purified buffer systems and produce optical artefacts in complex matrices such as whole‑blood.Here we report NREUL, a novel sensing paradigm based on nanoscale rare‑earth upconversion‑luminescence contact‑quenching. This mechanism relies on ligand‑relay and conformation‑modulated near‑field contact vibrational‑relaxation quenching, distinct from FRET‑type dipole‑dipole energy transfer. Rare‑earth upconversion nanocrystals are covalently anchored onto a quartz light‑guide rod to construct a solid‑phase sensing interface. Specific molecular recognition at the solid‑liquid interface remodels ligand conformation and rearranges interfacial hydration, building non‑radiative vibrational relaxation pathways and producing step‑wise luminescence decay, without requiring donor‑acceptor spectral overlap.We validated this sensing principle via multiple control experiments. Notably, resolvable kinetic signals were achieved directly in untreated anticoagulated human whole blood without centrifugation or dilution. NREUL supports both real‑time kinetic quantification and steady‑state endpoint quantification for molecular association‑dissociation analysis. It provides a new tool for observing solid‑liquid interfacial molecular dynamics in complex matrices, with application prospects spanning fundamental molecular‑interaction research, point‑of‑need sensing, bio‑agriculture and materials‑interface science.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 1,
  "authors": [
    {
      "name": "Lei Teng"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7rhx313fjarc6.bib",
  "cited_by": 0,
  "doi": "10.1149/osf.io/6n3hx_v1",
  "fulltext_url": null,
  "id": "7rhx313fjarc6",
  "issns": [],
  "landing_url": "https://osf.io/preprints/ecsarxiv/6n3hx_v1/",
  "language": null,
  "licence": "CC-BY-NC-ND",
  "licence_label": "CC BY-NC-ND",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "bepress",
      "Analytical Chemistry"
    ],
    [
      "bepress",
      "Chemistry"
    ],
    [
      "bepress",
      "Engineering"
    ],
    [
      "bepress",
      "Materials Science and Engineering"
    ],
    [
      "bepress",
      "Physical Sciences and Mathematics"
    ],
    [
      "openalex",
      "2505|Luminescence Properties of Advanced Materials"
    ]
  ],
  "openalex": "W7222233515",
  "pdf_url": "https://osf.io/6n3hx/download",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-15",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7rhx313fjarc6.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:52Z",
      "native_id": "6n3hx",
      "source": "osf",
      "url": "https://osf.io/preprints/ecsarxiv/6n3hx_v1/"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "bepress:Analytical Chemistry",
      "subfield": "analytical"
    }
  ],
  "title": "Nanoscale Rare-Earth Upconversion Contact-Quenching Sensing for Real-Time Molecular Detection in Complex Matrices",
  "title_text": "Nanoscale Rare-Earth Upconversion Contact-Quenching Sensing for Real-Time Molecular Detection in Complex Matrices",
  "type": "preprint",
  "updated_at": "2026-10-30T12:17:52Z",
  "url": "https://research.draconitic.com/paper/7rhx313fjarc6",
  "venue": "ECSarXiv",
  "versions": []
}